Quote: "can you re-place the cold breath with blood "
Anything is possible, but that would require more scripting for what you want to do. A more advanced scripter could do this for you as I am not very good at scripting. This script took me all day to make work right. Huds were not doing what I wanted and I had to ask a master for help.
I think for what you want would be more of if the player's health was below a certain point use this script. If I were to remake this script for what you are asking, I think I would add the pusling pain shader from Uzi with motion blur and make the camera look down at the ground use my script to spit up blood, shake the camera like the player is shaking it off and then return to a normal screen for a certain amount of time before starting all over again or until the player gains health.
That would be my thoughts, but again that would require a better scripter than me.